Physicochemical and biological studies of inclusion complex of methotrexate with β-cyclodextrin

Methotrexate forms an inclusion complex with β-cyclodextrin (β-CyD) by a neutralization method. The formation of the inclusion complex was studied by phase solubility, X-ray diffractometry, differential scanning calorimetry and infrared spectroscopy. The amino group of methotrexate interacted with the hydroxyl function of β-CyD on complexation. The in-vitro drug release from the complex in phosphate buffer, pH-7.2, was better than that of the plain drug and other preparations evaluated. The complex had better bioavailability and showed better antitumour efficacy than methotrexate alone.